Author Topic: Thoughts on oil in a marine engine  (Read 1633 times)

November 26, 2017, 06:22:06 pm

1.6Lmarine

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Thoughts on oil in a marine engine
« on: November 26, 2017, 06:22:06 pm »
So this 1.6l is done as soon at the new vacuum pump arrives

need to add oil and turn the engine to prime the fuel pump and injectors

any thoughts on the oil to use?

this is going on a 21' lobster boat displacement hull

marine engines are constantly under load

operating temps will be in cold northern waters here...they never warm up

the displacement hull operates most efficiently at 12 hp...and never planes

so this engine will operate at 1/4 max hp most of the time

any thoughts on which oil would work best?

and also i'd appreciate any insight on engine break-in procedures

again...block is fully rebuilt/rebored with a new head

thanks

1.6l marine



Reply #1November 26, 2017, 11:14:05 pm

ORCoaster

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    Restoring a Caddy as time and weather allows
Re: Thoughts on oil in a marine engine
« Reply #1 on: November 26, 2017, 11:14:05 pm »
Two thoughts to reckon with:

1. any thoughts on which oil would work best?
Rebuilt engine is going to wear, you know and want this.  So the first oil should just be some straight 30 W that you are going to properly dispose of in an environmentally friendly way right?  But how to figure that length of time?  Most break ins come with a 1,000 mile mark.  So for those on the water you use hours of engine time instead.  If I was driving for 1,000 miles there would be plenty of stop and go with a bit of highway madness thrown in for good measure.  But overall I doubt I would be averaging more than 35 miles an hour.  1,000 miles / 35 MPH = 28.5 hrs.  Just call it 30 and flip the oil and filter at that point in time or near to it depending on other convenient scheduling.

This next one is going to be harder for you to do being that you are water bound.

2. and also i'd appreciate any insight on engine break-in procedures
Normally you want the engine speed to vary from high to low RPM's and not have a constant set RPM going.  You wouldn't take a new engine out for a cross country trip and put 2500 miles on it going 65 mph for instance.  You would cycle the RPMs up and down the scale and use the back pressure of the engine when braking to lap in the new rings.  How can you best mimic that with a prop?  I don't think you can short of decreasing the speed. 

So I am going to suggest that you concentrate on the up and down of RPM's.  Not to the point that you get sick on the water, no one likes doing that.  But do some time at 1/8, 1/4, 1/2 and full throttle.  Take it up for awhile then down.  There is no need to get super fussy here.  Anything that changes the RPM's is better than straight shot throttle out to the destination and back without varying it.  Do folks like Yamaha or Honda suggest any particular break in process for their engines? 

After the initial break in I would just refill with some 15W 40 Rotella for diesels and again figure the hours.  A 3,000 mile interval would equate to about a 100 hr use, a 5, 000 interval a 150 hour.  I don't expect that you are in extreme environments like very dusty or very hot so no need to swap the oil more than normal.  Some might suggest that because it is rebuilt that you might be better off with some synthetic oil.  Possible but I would like to hear the reasons.  I am a simpleton for oil.  I do run synthetic in the new car but not in my Rabbit or Caddy.  Too old and worn at this point.  Besides I am cheap, and like to have an excuse to pop the hood and run the car up on ramps. 

Just some ideas I would throw out there for you and others to consider and comment on. 

By the time all opinions are in we might have a good process for you to follow. 

Catch many and only keep the big ones.  The others you come back for on another day remember that. 
« Last Edit: November 26, 2017, 11:17:40 pm by ORCoaster »